19-1230; Rev 2a; 6/97 KIT ATION EVALU E L B AVAILA 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown The MAX4223–MAX4228 are ideal for professional video applications, with differential gain and phase errors of 0.01% and 0.02°, 0.1dB gain flatness of 300MHz, and a 1100V/µs slew rate. Total harmonic distortion (THD) of -60dBc (10MHz) and an 8ns settling time to 0.1% suit these devices for driving high-speed analog-to-digital inputs or for data-communications applications. The lowpower shutdown mode on the MAX4223/MAX4224/ MAX4226/MAX4228 makes them suitable for portable and battery-powered applications. Their high output impedance in shutdown mode is excellent for multiplexing applications. The single MAX4223/MAX4224 are available in spacesaving 6-pin SOT23 packages. All devices are available in the extended -40°C to +85°C temperature range. ________________________Applications ADC Input Buffers Video Cameras Data Communications Video Line Drivers Video Switches Video Editors Video Multiplexing XDSL Drivers RF Receivers Differential Line Drivers _________________Pin Configurations ____________________________Features ♦ Ultra-High Speed and Fast Settling Time: 1GHz -3dB Bandwidth (MAX4223, Gain = +1) 600MHz -3dB Bandwidth (MAX4224, Gain = +2) 1700V/µs Slew Rate (MAX4224) 5ns Settling Time to 0.1% (MAX4224) ♦ Excellent Video Specifications (MAX4223): Gain Flatness of 0.1dB to 300MHz 0.01%/0.02° DG/DP Errors ♦ Low Distortion: -60dBc THD (fc = 10MHz) 42dBm Third-Order Intercept (f = 30MHz) ♦ 6.0mA Quiescent Supply Current (per amplifier) ♦ Shutdown Mode: 350µA Supply Current (per amplifier) 100kΩ Output Impedance ♦ High Output Drive Capability: 80mA Output Current Drives up to 4 Back-Terminated 75Ω Loads to ±2.5V while Maintaining Excellent Differential Gain/Phase Characteristics ♦ Available in Tiny 6-Pin SOT23 and 10-Pin µMAX Packages ______________Ordering Information PART TEMP. RANGE MAX4223EUT-T -40°C to +85°C 6 SOT23 MAX4223ESA 8 SO -40°C to +85°C 6 5 VEE 2 IN+ 3 Pin Configurations continued at end of data sheet. 4 SOT23-6 VCC SHDN IN- MAX4223 MAX4224 SOT TOP MARK AAAD — Ordering Information continued at end of data sheet. _____________________Selector Guide PART MIN. GAIN AMPS PER PKG. SHUTDOWN MODE PINPACKAGE MAX4223 1 1 Yes 6 SOT23, 8 SO MAX4224 2 1 Yes 6 SOT23, 8 SO MAX4225 1 2 No 8 SO 10 µMAX, 14 SO TOP VIEW OUT 1 PINPACKAGE MAX4226 1 2 Yes MAX4227 2 2 No 8 SO Yes 10 µMAX, 14 SO MAX4228 2 2 ________________________________________________________________ Maxim Integrated Products 1 For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800 For small orders, phone 408-737-7600 ext. 3468. MAX4223–MAX4228 _______________General Description The MAX4223–MAX4228 current-feedback amplifiers combine ultra-high-speed performance, low distortion, and excellent video specifications with low-power operation. The MAX4223/MAX4224/MAX4226/MAX4228 have a shutdown feature that reduces power-supply current to 350µA and places the outputs into a highimpedance state. These devices operate with dual supplies ranging from ±2.85V to ±5.5V and provide a typical output drive current of 80mA. The MAX4223/ MAX4225/MAX4226 are optimized for a closed-loop gain of +1 (0dB) or more and have a -3dB bandwidth of 1GHz, while the MAX4224/MAX4227/MAX4228 are compensated for a closed-loop gain of +2 (6dB) or more, and have a -3dB bandwidth of 600MHz (1.2GHz gain-bandwidth product). MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown ABSOLUTE MAXIMUM RATINGS Supply Voltage (VCC to VEE) ..................................................12V Analog Input Voltage .......................(VEE - 0.3V) to (VCC + 0.3V) Analog Input Current ........................................................±25mA SHDN Input Voltage.........................(VEE - 0.3V) to (VCC + 0.3V) Short-Circuit Duration OUT to GND ...........................................................Continuous OUT to VCC or VEE............................................................5sec Continuous Power Dissipation (TA = +70°C) 6-Pin SOT23 (derate 7.1mW/°C above +70°C).............571mW 8-Pin SO (derate 5.9mW/°C above +70°C)...................471mW 10-Pin µMAX (derate 5.6mW/°C above +70°C) ............444mW 14-Pin SO (derate 8.3mW/°C above +70°C).................667mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10sec) .............................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. DC ELECTRICAL CHARACTERISTICS (VCC = +5V, VEE = -5V, SHDN = 5V, VCM = 0V, RL = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL TA = +25°C Input Offset Voltage VOS TA = TMIN to TMAX Input Offset Voltage Drift Input Bias Current (Positive Input) Input Bias Current (Negative Input) TYP MAX MAX4223/MAX4224 ±0.5 ±4 MAX4225–MAX4228 ±0.5 ±5 CONDITIONS MIN MAX4223/MAX4224 ±6 MAX4225–MAX4228 ±2 TA = +25°C ±2 TA = TMIN to TMAX TA = +25°C IBTA = TMIN to TMAX mV ±7 TCVOS IB+ UNITS µV/°C ±10 ±15 MAX4223/MAX4224 ±4 MAX4225–MAX4228 ±4 MAX4223/MAX4224 ±20 ±25 ±30 MAX4225–MAX4228 µA µA ±35 Input Resistance (Positive Input) RIN+ 700 kΩ Input Resistance (Negative Input) RIN- 45 Ω Input Common-Mode Voltage Range VCM ±2.5 ±3.2 V TA = +25°C 55 61 TA = TMIN to TMAX 50 Common-Mode Rejection Ratio Operating Supply Voltage Range Power-Supply Rejection Ratio CMRR VCC/VEE PSRR Quiescent Supply Current (per Amplifier) ISY Open-Loop Transresistance TR Inferred from CMRR test VCM = ±2.5V Inferred from PSRR test VCC = 2.85V to 5.5V, VEE = -2.85V to -5.5V 9.0 VOUT = ±2.5V VIL 2 V dB 0.55 RL = 50Ω VIH 63 6.0 IOUT SHDN Logic High TA = TMIN to TMAX 74 0.35 VOUT SHDN Logic Low 68 Shutdown mode (SHDN = 0V) RL = ∞ VOUT = ±2.5V RL = 50Ω Output Current (Note 2) ISC TA = +25°C ±5.5 Normal mode (SHDN = 5V) Output Voltage Swing Short-Circuit Output Current ±2.85 dB mA 0.7 1.5 0.3 0.8 ±2.5 ±2.8 V 60 80 mA 140 mA RL = short to ground MΩ 0.8 2.0 _______________________________________________________________________________________ V V 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown (VCC = +5V, VEE = -5V, SHDN = 5V, VCM = 0V, RL = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SHDN Input Current SYMBOL IIL/IIH CONDITIONS MIN SHDN = 0V or 5V SHDN = 0V, VOUT = -2.5V to +2.5V (Note 3) Shutdown Mode Output Impedance 10 TYP MAX UNITS 25 70 µA 100 kΩ AC ELECTRICAL CHARACTERISTICS (VCC = +5V, VEE = -5V, SHDN = 5V, VCM = 0V, AV = +1V/V for MAX4223/MAX4225/MAX4226, AV = +2V/V for MAX4224/MAX4227/ MAX4228, RL = 100Ω, TA = +25°C, unless otherwise noted.) (Note 4) PARAMETER -3dB Small-Signal Bandwidth (Note 5) Bandwidth for ±0.1dB Gain Flatness (Note 5) SYMBOL BW VOUT = 20mVp-p BW0.1dB VOUT = 20mVp-p Gain Peaking Large-Signal Bandwidth CONDITIONS BWLS SR Rise and Fall Time MAX4223/5/6 750 1000 MAX4224/7/8 325 600 MAX4223/5/6 100 300 MAX4224/7/8 60 200 1.5 MAX4224/7/8 0.1 VOUT = 2Vp-p VOUT = 4V step Falling edge Settling Time to 0.1% TYP MAX4223/5/6 Rising edge Slew Rate (Note 5) MIN tS VOUT = 2V step tr, tf VOUT = 2V step MAX4223/5/6 250 MAX4224/7/8 330 MAX4223/5/6 850 1100 MAX4224/7/8 1400 1700 MAX4223/5/6 625 800 MAX4224/7/8 1100 1400 MAX4223/5/6 8 MAX4224/7/8 5 MAX4223/5/6 1.5 MAX4224/7/8 1.0 SHDN = 0V, f = 10MHz, MAX4223/4/6/8 Off Isolation Crosstalk XTALK f = 30MHz, RS = 50Ω 65 MAX4225/6 -68 MAX4227/8 -72 MAX UNITS MHz MHz dB MHz V/µs ns ns dB dB Turn-On Time from Shutdown tON MAX4223/4/6/8 2 µs Turn-Off Time to Shutdown tOFF MAX4223/4/6/8 300 ns Power-Up Time tUP VCC, VEE = 0V to ±5V step 100 ns Differential Gain Error DG RL = 150Ω (Note 6) Differential Phase Error DP RL = 150Ω (Note 6) Total Harmonic Distortion THD VOUT = 2Vp-p, fC = 10MHz RL = 100Ω RL = 1kΩ MAX4223/5/6 0.01 MAX4224/7/8 0.02 MAX4223/5/6 0.02 MAX4224/7/8 0.01 MAX4223/5/6 -60 MAX4224/7/8 -61 MAX4223/5/6 -65 MAX4224/7/8 -78 % degrees dBc _______________________________________________________________________________________ 3 MAX4223–MAX4228 DC ELECTRICAL CHARACTERISTICS (continued) AC ELECTRICAL CHARACTERISTICS (continued) (VCC = +5V, VEE = -5V, SHDN = 5V, VCM = 0V, AV = +1V/V for MAX4223/MAX4225/MAX4226, AV = +2V/V for MAX4224/MAX4227/ MAX4228, RL = 100Ω, TA = +25°C, unless otherwise noted.) (Note 4) PARAMETER SYMBOL Output Impedance ZOUT Third-Order Intercept CONDITIONS MIN TYP f = 10kHz SFDR f = 10kHz 1dB Gain Compression MAX MAX4223/5/6 42 MAX4224/7/8 36 MAX4223/5/6 -61 MAX4224/7/8 -62 UNITS Ω 2 f = 30kHz fz = 30.1MHz IP3 Spurious-Free Dynamic Range dBm dB f = 10kHz 20 dBm Input Noise Voltage Density en f = 10kHz 2 nV/√Hz Input Noise Current Density in+, in- f = 10kHz Input Capacitance (Note 7) CIN IN+ 3 IN- 20 SO-8, SO-14 packages Pin to pin 0.3 Pin to GND 1.0 SOT23-6, 10-pin µMAX packages Pin to pin 0.3 Pin to GND 0.8 pA/√Hz pF The MAX422_EUT is 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design. Absolute Maximum Power Dissipation must be observed. Does not include impedance of external feedback resistor network. AC specifications shown are with optimal values of RF and RG. These values vary for product and package type, and are tabulated in the Applications Information section of this data sheet. Note 5: The AC specifications shown are not measured in a production test environment. The minimum AC specifications given are based on the combination of worst-case design simulations along with a sample characterization of units. These minimum specifications are for design guidance only and are not intended to guarantee AC performance (see AC Testing/ Performance). For 100% testing of these parameters, contact the factory. Note 6: Input Test Signal: 3.58MHz sine wave of amplitude 40IRE superimposed on a linear ramp (0IRE to 100IRE). IRE is a unit of video signal amplitude developed by the International Radio Engineers. 140IRE = 1V. Note 7: Assumes printed circuit board layout similar to that of Maxim’s evaluation kit. Note 1: Note 2: Note 3: Note 4: __________________________________________Typical Operating Characteristics (VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.) MAX4223 SMALL-SIGNAL GAIN vs. FREQUENCY (AVCL = +2/+5) NORMALIZED GAIN (dB) 2 2 1 0 -1 SOT23-6 RF = 470Ω -2 -3 0 -1 -2 AV = +5V/V RF = 100Ω RG = 25Ω -3 1 0 -1 -2 -3 -4 -4 -4 -5 -5 -5 -6 -6 1 10 100 FREQUENCY (MHz) 4 2 AV = +2V/V RF = RG = 200Ω 1 1000 AV = +1V/V RF = 560Ω VOUT = 2Vp-p 3 GAIN (dB) SO-8 PACKAGE RF = 560Ω VIN = 20mVp-p 3 4 MAX4223-02 VIN = 20mVp-p 3 4 MAX4223-01 4 MAX4223/MAX4225/MAX4226 LARGE-SIGNAL GAIN vs. FREQUENCY (AVCL = +1) MAX4223-03 MAX4223 SMALL-SIGNAL GAIN vs. FREQUENCY (AVCL = +1) GAIN (dB) MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown -6 1 10 100 FREQUENCY (MHz) 1000 1 10 100 FREQUENCY (MHz) _______________________________________________________________________________________ 1000 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown MAX4224 SMALL-SIGNAL GAIN vs. FREQUENCY (AVCL = +5/+10) VIN = 20mVp-p 3 AVCL = +5V/V RF = 240Ω RG = 62Ω 0 -1 -2 SO-8 PACKAGE RF = RG = 470Ω SOT23-6 PACKAGE RF = RG = 470Ω -5 10 100 AVCL = +10V/V RF = 130Ω RG = 15Ω -2 -3 -4 -6 1 1000 10 1000 1 0.4 MAX4223-07 VIN = 20mVp-p AVCL = +1V/V RF = 560Ω VIN = 2OmVp-p AVCL = +1V/V RF = 560Ω 0.3 0.2 GAIN (dB) 0 -1 -2 -3 AMPLIFIER A 0 AMPLIFIER B -0.3 0 -1 -2 -3 -4 -0.4 -4 -0.5 -5 10 100 10 1 100 100 1000 FREQUENCY (MHz) MAX4227/MAX4228 GAIN MATCHING vs. FREQUENCY (AVCL = +2) MAX4225/MAX4226 CROSSTALK vs. FREQUENCY MAX4227/MAX4228 CROSSTALK vs. FREQUENCY -0.2 -20 -20 -30 -30 -40 -50 -60 -60 -0.4 -80 -80 -0.5 -90 -90 -100 -100 -0.6 1 10 FREQUENCY (MHz) 100 MAX4223-12 -40 -50 -70 -70 -0.3 RS = 50Ω VOUT = 2Vp-p -10 CROSSTALK (dB) CROSSTALK (dB) 0 -0.1 RS = 50Ω VOUT = 2Vp-p -10 0 MAX4223-11 0 MAX4223-10 0.1 0.1 10 FREQUENCY (MHz) VIN = 20mVp-p AVCL = +2V/V RF = RG = 470Ω 0.2 1 FREQUENCY (MHz) 0.4 0.3 -6 -0.6 1000 VIN = 20mVp-p AVCL = +2V/V RF = RG = 470Ω 1 -5 -6 1000 4 3 2 -0.1 -0.2 100 MAX4227/MAX4228 SMALL-SIGNAL GAIN vs. FREQUENCY (AVCL = +2) 0.1 1 10 FREQUENCY (MHz) MAX4225/MAX4226 GAIN MATCHING vs. FREQUENCY (AVCL = +1) 1 GAIN (dB) 100 FREQUENCY (MHz) 4 NORMALIZED GAIN (dB) -2 -3 -5 MAX4225/MAX4226 SMALL-SIGNAL GAIN vs. FREQUENCY (AVCL = +1) 2 0 -1 -5 FREQUENCY (MHz) 3 1 -4 -6 -6 1 -1 NORMALIZED GAIN (dB) -4 0 MAX4223-08 -3 2 MAX4223-09 NORMALIZED GAIN (dB) 1 AVCL = +2V/V RF = RG = 470Ω VOUT = 2Vp-p 3 NORMALIZED GAIN (dB) 2 1 4 MAX4223-05 VIN = 20mVp-p 2 NORMALIZED GAIN (dB) 4 MAX4223-04 4 3 MAX4224/MAX4227/MAX4228 LARGE-SIGNAL GAIN vs. FREQUENCY (AVCL = +2) MAX4223-06 MAX4224 SMALL-SIGNAL GAIN vs. FREQUENCY (AVCL = +2) 1 10 100 FREQUENCY (MHz) 1000 1 10 100 1000 FREQUENCY (MHz) _______________________________________________________________________________________ 5 MAX4223–MAX4228 ____________________________Typical Operating Characteristics (continued) (VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.) ____________________________Typical Operating Characteristics (continued) (VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.) MAX4224/MAX4227/MAX4228 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY (AVCL = +2) -10 -20 -20 -30 VCC -50 -60 VCC -40 -50 -60 VEE -70 VEE -70 -80 10 MAX4223/5/6 AVCL = +1V/V RF = 560Ω 1 MAX4224/7/8 AVCL = +2V/V RF = RG = 470Ω 0.1 -80 -90 -90 0.01 0.1 1 10 100 0.01 0.01 0.1 1 10 100 0.01 0.1 1 10 100 FREQUENCY (MHz) FREQUENCY (MHz) FREQUENCY (MHz) SHUTDOWN MODE OUTPUT ISOLATION vs. FREQUENCY MAX4223/MAX4225/MAX4226 TOTAL HARMONIC DISTORTION vs. FREQUENCY (RL = 150Ω) MAX4223/MAX4225/MAX4226 TOTAL HARMONIC DISTORTION vs. FREQUENCY (RL = 1kΩ) -40 THD (dBc) -80 MAX4224/7/8 AVCL = +2V/V RF = RG = 470Ω -120 -60 2ND HARMONIC -80 0.1 1 10 100 -90 -100 -90 1000 0.1 10 1 0.1 100 10 1 100 FREQUENCY (MHz) FREQUENCY (MHz) FREQUENCY (MHz) MAX4224/MAX4227/MAX4228 TOTAL HARMONIC DISTORTION vs. FREQUENCY (RL = 150Ω) MAX4224/MAX4227/MAX4228 TOTAL HARMONIC DISTORTION vs. FREQUENCY (RL = 1kΩ) TWO-TONE THIRD-ORDER INTERCEPT vs. FREQUENCY -40 -50 THD THD (dBc) -50 -60 -60 -70 THD -70 2ND HARMONIC 2ND HARMONIC -80 3RD HARMONIC MAX4223-21 -40 55 THIRD-ORDER INTERCEPT (dBm) -30 MAX4223-19 -30 -80 3RD HARMONIC 3RD HARMONIC MAX4223-20 0.01 -70 -80 -160 -180 THD -60 2ND HARMONIC -70 -140 AVCL = +1V/V RL = 1kΩ RF = 560Ω VOUT = 2Vp-p -40 -50 THD MAX4223-18 -40 -50 -60 -100 AVCL = +1V/V RL = 150Ω RF = 560Ω VOUT = 2Vp-p THD (dBc) MAX4223/5/6 AVCL = +1V/V RF = 560Ω -30 MAX4223-17 0 -20 -30 MAX4223-16 20 SHUTDOWN MODE OUTPUT ISOLATION (dB) -30 OUTPUT IMPEDANCE (Ω) -10 -40 AVCL = +2V/V RF = RG = 470Ω 0 100 MAX4223-14 AVCL = +1V/V RF = 560Ω PSRR (dB) PSRR (dB) 0 OUTPUT IMPEDANCE vs. FREQUENCY 10 MAX4223-13 10 MAX4223-15 MAX4223/MAX4225/MAX4226 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY (AVCL = +1) THD (dBc) MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown 50 45 MAX4224/7/8 40 35 30 MAX4223/5/6 25 -90 3RD HARMONIC -90 0.1 1 10 FREQUENCY (MHz) 6 20 -100 100 0.1 1 10 FREQUENCY (MHz) 100 10 20 30 40 50 60 70 FREQUENCY (MHz) _______________________________________________________________________________________ 80 90 100 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown MAX4223/MAX4225/MAX4226 SMALL-SIGNAL PULSE RESPONSE (AVCL = +1) MAX4224/MAX4227/MAX4228 SMALL-SIGNAL PULSE RESPONSE (AVCL = +2) MAX4223/MAX4225/MAX4226 SMALL-SIGNAL PULSE RESPONSE (AVCL = +1, CL = 25pF) MAX4223-22 MAX4223-24 MAX4223-23 +100mV +50mV +100mV GND INPUT GND INPUT -100mV +100mV GND OUTPUT -100mV GND INPUT -100mV -50mV +100mV +100mV OUTPUT GND OUTPUT -100mV -100mV GND TIME (10ns/div) TIME (10ns/div) TIME (10ns/div) MAX4224/MAX4227/MAX4228 SMALL-SIGNAL PULSE RESPONSE (AVCL = +2, CL = 10pF) MAX4223/MAX4225/MAX4226 LARGE-SIGNAL PULSE RESPONSE (AVCL = +1) MAX4223/MAX4225/MAX4226 LARGE-SIGNAL PULSE RESPONSE (AVCL = +1, CL = 25pF) MAX4223-25 MAX4223-27 MAX4223-26 +50mV +2V +2V GND INPUT -50mV +100mV GND OUTPUT -100mV GND INPUT GND INPUT -2V -2V +2V +2V OUTPUT GND OUTPUT -2V -2V GND TIME (10ns/div) TIME (10ns/div) TIME (10ns/div) MAX4224/MAX4227/MAX4228 LARGE-SIGNAL PULSE RESPONSE (AVCL = +2) MAX4224/MAX4227/MAX4228 LARGE-SIGNAL PULSE RESPONSE (AVCL = +2,CL = 10pF) MAX4224/MAX4227/MAX4228 LARGE-SIGNAL PULSE RESPONSE (AVCL = +5) MAX4223-28 MAX4223-30 MAX4223-29 +1V +400mV +1V INPUT GND INPUT GND INPUT -1V -1V -400mV +2V +2V +2V OUTPUT GND OUTPUT -2V -2V GND OUTPUT -2V TIME (10ns/div) TIME (10ns/div) GND GND TIME (10ns/div) _______________________________________________________________________________________ 7 MAX4223–MAX4228 ____________________________Typical Operating Characteristics (continued) (VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.) ____________________________Typical Operating Characteristics (continued) (VCC = +5V, VEE = -5V, RL = 100Ω, TA = +25°C, unless otherwise noted.) NORMAL MODE 160 4 5 4 3 CURRENT (mA) SINKING CURRENT (µA) 6 3 IB2 150 140 SOURCING IB+ 2 130 1 SHUTDOWN MODE 1 0 120 0 -50 -25 0 25 50 75 100 -25 -50 TEMPERATURE (°C) 0 25 50 75 3.0 75 RL = 50Ω 2.5 2.0 1.5 MAX4223-35 -1.0 -1.5 NEGATIVE OUTPUT SWING (V) RL = OPEN 3.5 50 NEGATIVE OUTPUT SWING vs. TEMPERATURE MAX4223-34 4.0 25 TEMPERATURE (°C) TEMPERATURE (°C) 4.5 POSITIVE OUTPUT SWING (V) 0 -25 -50 100 POSITIVE OUTPUT SWING vs. TEMPERATURE -2.0 -2.5 RL = 50Ω -3.0 -3.5 RL = OPEN -4.0 1.0 -4.5 -50 -25 0 25 50 TEMPERATURE (°C) 8 MAX4223-33 7 170 MAX4223-32 5 MAX4223-31 8 SHORT-CIRCUIT OUTPUT CURRENT vs. TEMPERATURE INPUT BIAS CURRENT vs. TEMPERATURE POWER-SUPPLY CURRENT PER AMPLIFIER vs. TEMPERATURE CURRENT (mA) MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown 75 100 -50 -25 0 25 50 TEMPERATURE (°C) _______________________________________________________________________________________ 75 100 100 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown PIN MAX4223/MAX4224 MAX4225 MAX4227 MAX4226/MAX4228 NAME FUNCTION FUNCTION SOT23 SO SO µMAX SO — 1, 5 — — 5, 7, 8, 10 N.C. No Connect. Not internally connected. Tie to GND for optimum AC performance. 1 6 — — — OUT Amplifier Output 2 4 4 4 4 VEE Negative Power-Supply Voltage. Connect to -5V. 3 3 — — — IN+ Amplifier Noninverting Input 4 2 — — — IN- Amplifier Inverting Input Amplifier Shutdown. Connect to +5V for normal operation. Connect to GND for lowpower shutdown. 5 8 — — — SHDN 6 7 8 10 14 VCC — — 1 1 1 OUTA — — 2 2 2 INA- Amplifier A Inverting Input — — 3 3 3 INA+ Amplifier A Noninverting Input — — 5 7 11 INB+ Amplifier B Noninverting Input — — 6 8 12 INB- Amplifier B Inverting Input — — 7 9 13 OUTB — — — 5 6 — — — 6 9 Positive Power-Supply Voltage. Connect to +5V. Amplifier A Output Amplifier B Output SHDNA Amplifier A Shutdown Input. Connect to +5V for normal operation. Connect to GND for low-power shutdown mode. SHDNB Amplifier B Shutdown Input. Connect to +5V for normal operation. Connect to GND for low-power shutdown mode. _______________________________________________________________________________________ 9 MAX4223–MAX4228 ______________________________________________________________Pin Description MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown _______________Detailed Description The MAX4223–MAX4228 are ultra-high-speed, lowpower, current-feedback amplifiers featuring -3dB bandwidths up to 1GHz, 0.1dB gain flatness up to 300MHz, and very low differential gain and phase errors of 0.01% and 0.02°, respectively. These devices operate on dual ±5V or ±3V power supplies and require only 6mA of supply current per amplifier. The MAX4223/MAX4225/MAX4226 are optimized for closed-loop gains of +1 (0dB) or more and have -3dB bandwidths of 1GHz. The MAX4224/MAX4227/ MAX4228 are optimized for closed-loop gains of +2 (6dB) or more, and have -3dB bandwidths of 600MHz (1.2GHz gain-bandwidth product). The current-mode feedback topology of these amplifiers allows them to achieve slew rates of up to 1700V/µs with corresponding large signal bandwidths up to 330MHz. Each device in this family has an output that is capable of driving a minimum of 60mA of output current to ±2.5V. RG RF IN- RINTZ OUT +1 +1 IN+ MAX4223 MAX4224 MAX4225 MAX4226 MAX4227 MAX4228 VIN Theory of Operation Since the MAX4223–MAX4228 are current-feedback amplifiers, their open-loop transfer function is expressed as a transimpedance: ∆VOUT or TZ ∆IIN − The frequency behavior of this open-loop transimpedance is similar to the open-loop gain of a voltage-feedback amplifier. That is, it has a large DC value and decreases at approximately 6dB per octave. Analyzing the current-feedback amplifier in a gain configuration (Figure 1) yields the following transfer function: () TZ S VOUT =G x VIN TZ S + G x RIN − + RF R where G = A V = 1 + F . RG () At low gains, (G x RIN-) << RF . Therefore, unlike traditional voltage-feedback amplifiers, the closed-loop bandwidth is essentially independent of the closedloop gain. Note also that at low frequencies, TZ >> [(G x RIN-) + RF], so that: VOUT R = G = 1+ F VIN RG 10 Figure 1. Current-Feedback Amplifier Low-Power Shutdown Mode The MAX4223/MAX4224/MAX4226/MAX4228 have a shutdown mode that is activated by driving the SHDN input low. When powered from ±5V supplies, the SHDN input is compatible with TTL logic. Placing the amplifier in shutdown mode reduces quiescent supply current to 350µA typical, and puts the amplifier output into a highimpedance state (100kΩ typical). This feature allows these devices to be used as multiplexers in wideband systems. To implement the mux function, the outputs of multiple amplifiers can be tied together, and only the amplifier with the selected input will be enabled. All of the other amplifiers will be placed in the low-power shutdown mode, with their high output impedance presenting very little load to the active amplifier output. For gains of +2 or greater, the feedback network impedance of all the amplifiers used in a mux application must be considered when calculating the total load on the active amplifier output. __________Applications Information Layout and Power-Supply Bypassing The MAX4223–MAX4228 have an extremely high bandwidth, and consequently require careful board layout, including the possible use of constant-impedance microstrip or stripline techniques. ______________________________________________________________________________________ 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown 1) Do not use wire-wrapped boards (they are too inductive) or breadboards (they are too capacitive). 2) Do not use IC sockets. IC sockets increase reactance. 3) Keep signal lines as short and straight as possible. Do not make 90° turns; round all corners. 4) Observe high-frequency bypassing techniques to maintain the amplifier’s accuracy and stability. 5) In general, surface-mount components have shorter bodies and lower parasitic reactance, giving better high-frequency performance than through-hole components. The bypass capacitors should include a 10nF ceramic, surface-mount capacitor between each supply pin and the ground plane, located as close to the package as possible. Optionally, place a 10µF tantalum capacitor at the power-supply pins’ point of entry to the PC board to ensure the integrity of incoming supplies. The powersupply trace should lead directly from the tantalum capacitor to the VCC and VEE pins. To minimize parasitic inductance, keep PC traces short and use surfacemount components. The N.C. pins should be connected to a common ground plane on the PC board to minimize parasitic coupling. If input termination resistors and output back-termination resistors are used, they should be surface-mount types, and should be placed as close to the IC pins as possible. Tie all N.C. pins to the ground plane to minimize parasitic coupling. Choosing Feedback and Gain Resistors As with all current-feedback amplifiers, the frequency response of these devices depends critically on the value of the feedback resistor RF. RF combines with an internal compensation capacitor to form the dominant pole in the feedback loop. Reducing R F ’s value increases the pole frequency and the -3dB bandwidth, but also increases peaking due to interaction with other nondominant poles. Increasing R F ’s value reduces peaking and bandwidth. Table 1 shows optimal values for the feedback resistor (RF) and gain-setting resistor (RG) for the MAX4223– MAX4228. Note that the MAX4224/MAX4227/MAX4228 offer superior AC performance for all gains except unity gain (0dB). These values provide optimal AC response using surface-mount resistors and good layout techniques. Maxim’s high-speed amplifier evaluation kits provide practical examples of such layout techniques. Stray capacitance at IN- causes feedback resistor decoupling and produces peaking in the frequencyresponse curve. Keep the capacitance at IN- as low as possible by using surface-mount resistors and by avoiding the use of a ground plane beneath or beside these resistors and the IN- pin. Some capacitance is unavoidable; if necessary, its effects can be counteracted by adjusting RF. Use 1% resistors to maintain consistency over a wide range of production lots. Table 1. Optimal Feedback Resistor Networks GAIN (V/V) GAIN (dB) RF (Ω) RG (Ω) -3dB BW (MHz) 0.1dB BW (MHz) MAX4223/MAX4225/MAX4226 1 0 560* Open 1000 300 2 6 200 200 380 115 5 14 100 25 235 65 MAX4224/MAX4227/MAX4228 2 6 470 470 600 200 5 14 240 62 400 90 10 20 130 15 195 35 *For the MAX4223EUT, this optimal value is 470Ω. ______________________________________________________________________________________ 11 MAX4223–MAX4228 To realize the full AC performance of these high-speed amplifiers, pay careful attention to power-supply bypassing and board layout. The PC board should have at least two layers: a signal and power layer on one side and a large, low-impedance ground plane on the other. The ground plane should be as free of voids as possible, with one exception: the inverting input pin (IN-) should have as low a capacitance to ground as possible. This means that there should be no ground plane under IN- or under the components (RF and RG) connected to it. With multilayer boards, locate the ground plane on a layer that incorporates no signal or power traces. Whether or not a constant-impedance board is used, it is best to observe the following guidelines when designing the board: MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown DC and Noise Errors The MAX4223–MAX4228 output offset voltage, V OUT (Figure 2), can be calculated with the following equation: ( RG ) VOUT = VOS x 1 + RF /RG + IB + x RS RF IN- RF x 1 + + IB − x RF R G IB- OUT VOUT where: VOS = input offset voltage (in volts) 1 + RF / RG = amplifier closed-loop gain (dimensionless) IB+ = input bias current (in amps) IB- = inverting input bias current (in amps) RG = gain-setting resistor (in Ω) RF = feedback resistor (in Ω) RS = source resistor (in Ω) IB+ IN+ MAX4223 MAX4224 MAX4225 MAX4226 MAX4227 MAX4228 RS Figure 2. Output Offset Voltage The following equation represents output noise density: RF en(OUT) = 1 + x RG (in + x RS )2 [ ( + in − x RF || RG )] +(en )2 2 where: in = input noise current density (in pA/√Hz) en = input noise voltage density (in nV/√Hz) The MAX4223–MAX4228 have a very low, 2nV/√Hz noise voltage. The current noise at the noninverting input (in+) is 3pA/√Hz, and the current noise at the inverting input (in-) is 20pA/√Hz. An example of DC-error calculations, using the MAX4224 typical data and the typical operating circuit with RF = RG = 470Ω (RF || RG = 235Ω) and RS = 50Ω, gives: VOUT = [5 x 10-4 x (1 + 1)] + [2 x 10-6 x 50 x (1 + 1)] + [4 x 10-6 x 470] VOUT = 3.1mV Calculating total output noise in a similar manner yields the following: ( ) en(OUT) = 1 + 1 x 2 2 20 x 10 −12 x 235 + 2 x 10 −9 12 Communication Systems Nonlinearities of components used in a communication system produce distortion of the desired output signal. Intermodulation distortion (IMD) is the distortion that results from the mixing of two input signals of different frequencies in a nonlinear system. In addition to the input signal frequencies, the resulting output signal contains new frequency components that represent the sum and difference products of the two input frequencies. If the two input signals are relatively close in frequency, the third-order sum and difference products will fall close to the frequency of the desired output and will therefore be very difficult to filter. The third-order intercept (IP3) is defined as the power level at which the amplitude of the largest third-order product is equal to the power level of the desired output signal. Higher third-order intercept points correspond to better linearity of the amplifier. The MAX4223–MAX4228 have a typical IP3 value of 42dBm, making them excellent choices for use in communications systems. ADC Input Buffers 3 2 −12 x 10 x 50 + en(OUT) = 10.2nV / Hz With a 600MHz system bandwidth, this calculates to 250µV RMS (approximately 1.5mVp-p, using the sixsigma calculation). Input buffer amplifiers can be a source of significant errors in high-speed ADC applications. The input buffer is usually required to rapidly charge and discharge the ADC’s input, which is often capacitive (see the section Driving Capacitive Loads). In addition, a high-speed ADC’s input impedance often changes very rapidly during the conversion cycle, requiring an amplifier with ______________________________________________________________________________________ 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown small gain error. At higher capacitive loads, AC performance is limited by the interaction of load capacitance with the isolation resistor. Video Line Driver Figures 7 and 8 show a suggested layout for Maxim’s high-speed, single-amplifier evaluation boards. These boards were developed using the techniques described above. The smallest available surface-mount resistors were used for the feedback and back-termination resistors to minimize the distance from the IC to these resistors, thus reducing the capacitance associated with longer lead lengths. SMA connectors were used for best high-frequency performance. Because distances are extremely short, performance is unaffected by the fact that inputs and outputs do not match a 50Ω line. However, in applications that require lead lengths greater than 1/4 of the wavelength of the highest frequency of interest, constant-impedance traces should be used. Fully assembled evaluation boards are available for the MAX4223 in an SO-8 package. The MAX4223–MAX4228 are optimized to drive coaxial transmission lines when the cable is terminated at both ends, as shown in Figure 3. Note that cable frequency response may cause variations in the signal’s flatness. Driving Capacitive Loads A correctly terminated transmission line is purely resistive and presents no capacitive load to the amplifier. Although the MAX4223–MAX4228 are optimized for AC performance and are not designed to drive highly capacitive loads, they are capable of driving up to 25pF without excessive ringing. Reactive loads decrease phase margin and may produce excessive ringing and oscillation (see Typical Operating Characteristics). Figure 4’s circuit reduces the effect of large capacitive loads. The small (usually 5Ω to 20Ω) isolation resistor RISO, placed before the reactive load, prevents ringing and oscillation at the expense of a RG RF RG Maxim’s High-Speed Evaluation Board Layout RF INOUT 75Ω CABLE RT 75Ω 75Ω CABLE IN- OUT IN+ MAX4223 MAX4224 MAX4225 MAX4226 MAX4227 MAX4228 RT 75Ω Figure 3. Video Line Driver RT 75Ω RISO CL IN+ RL MAX4223 MAX4224 MAX4225 MAX4226 MAX4227 MAX4228 Figure 4. Using an Isolation Resistor (RISO) for High Capacitive Loads ______________________________________________________________________________________ 13 MAX4223–MAX4228 very low output impedance at high frequencies to maintain measurement accuracy. The combination of high speed, fast slew rate, low noise, and low distortion makes the MAX4223–MAX4228 ideally suited for use as buffer amplifiers in high-speed ADC applications. -3dB BANDWIDTH (MHz) 40 RISING-EDGE SLEW RATE (V/µs) Figure 5c. MAX4223 Rising-Edge Slew-Rate Distribution 400–420 925–950 875–900 825–850 775–800 725–750 0–500 1225–1250 1175–1200 1125–1150 1075–1100 975–1000 0 1025–1050 0 925–950 10 875–900 10 675–700 20 625–650 20 SIMULATION LOWER LIMIT 30 575–600 SIMULATION LOWER LIMIT MAX4223-fig5d 100 UNITS NUMBER OF UNITS 40 0–800 360–380 50 525–550 100 UNITS 825–850 320–340 Figure 5b. MAX4223 ±0.1dB Bandwidth Distribution MAX4223-fig5c 50 14 280–300 ±0.1dB BANDWIDTH (MHz) Figure 5a. MAX4223 -3dB Bandwidth Distribution 30 240–260 0–60 1450–1500 1350–1400 1250–1300 1150–1200 1050–1100 950–1000 0 850–900 0 750–800 10 200–220 20 10 0–600 SIMULATION LOWER LIMIT 30 160–180 20 MAX4223-fig5b 100 UNITS 40 NUMBER OF UNITS SIMULATION LOWER LIMIT 650–700 NUMBER OF UNITS 40 120–140 100 UNITS 30 50 MAX4223-fig5a 50 manufacturers guarantee AC specifications without clearly stating how this guarantee is made. The MAX4223–MAX4228 AC specifications are derived from worst-case design simulations combined with a sample characterization of 100 units. The AC performance distributions along with the worst-case simulation limits are shown in Figures 5 and 6. These distributions are repeatable provided that proper board layout and power-supply bypassing are used (see Layout and Power-Supply Bypassing section). 80–100 AC Testing/Performance AC specifications on high-speed amplifiers are usually guaranteed without 100% production testing. Since these high-speed devices are sensitive to external parasitics introduced when automatic handling equipment is used, it is impractical to guarantee AC parameters through volume production testing. These parasitics are greatly reduced when using the recommended PC board layout (like the Maxim evaluation kit). Characterizing the part in this way more accurately represents the amplifier’s true AC performance. Some NUMBER OF UNITS MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown FALLING-EDGE SLEW RATE (V/µs) Figure 5d. MAX4223 Falling-Edge Slew-Rate Distribution ______________________________________________________________________________________ 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown 40 -3dB BANDWIDTH (MHz) Figure 6c. MAX4224 Rising-Edge Slew-Rate Distribution 380–400 MAX4223-fig6d 1525–1550 1475–1500 1425–1450 1375–1400 1325–1350 1275–1300 1825–1850 1775–1800 1725–1750 1675–1700 0 1625–1650 0 1575–1600 10 1225–1250 20 10 RISING-EDGE SLEW RATE (V/µs) SIMULATION LOWER LIMIT 30 1175–1200 20 1525–1550 340–360 40 0–1100 SIMULATION LOWER LIMIT 1475–1500 300–320 100 UNITS NUMBER OF UNITS 40 0–1400 260–280 50 1125–1150 100 UNITS 1425–1450 220–240 Figure 6b. MAX4224 ±0.1dB Bandwidth Distribution MAX4223-fig6c 50 NUMBER OF UNITS 180–200 ±0.1dB BANDWIDTH (MHz) Figure 6a. MAX4224 -3dB Bandwidth Distribution 30 140–160 0–40 1050–1100 850–900 950–1000 750–800 650–700 550–600 0 450–500 0 350–400 10 100–120 20 10 0–200 SIMULATION LOWER LIMIT 30 60–80 20 MAX4223-fig6b 100 UNITS NUMBER OF UNITS SIMULATION LOWER LIMIT 250–300 NUMBER OF UNITS 40 30 50 MAX4223-fig6a 100 UNITS MAX4223–MAX4228 50 FALLING-EDGE SLEW RATE (V/µs) Figure 6d. MAX4224 Falling-Edge Slew-Rate Distribution ______________________________________________________________________________________ 15 MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown Figure 7a. Maxim SOT23 High-Speed Evaluation Board Component Placement Guide—Component Side Figure 7b. Maxim SOT23 High-Speed Evaluation Board PC Board Layout—Component Side 16 Figure 7c. Maxim SOT23 High-Speed Evaluation Board PC Board Layout—Back Side ______________________________________________________________________________________ 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown MAX4223–MAX4228 Figure 8a. Maxim SO-8 High-Speed Evaluation Board Component Placement Guide—Component Side Figure 8b. Maxim SO-8 High-Speed Evaluation Board PC Board Layout—Component Side Figure 8c. Maxim SO-8 High-Speed Evaluation Board PC Board Layout—Back Side ______________________________________________________________________________________ 17 MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown _____________________________________________Pin Configurations (continued) TOP VIEW MAX4223 MAX4224 MAX4225 MAX4227 N.C. 1 8 SHDN IN- 2 7 IN+ 3 VEE 4 OUTA 1 8 VCC VCC INA- 2 7 OUTB 6 OUT INA+ 3 6 INB- 5 N.C. VEE 4 5 INB+ SO SO MAX4226 MAX4228 MAX4226 MAX4228 10 VCC OUTA 1 OUTA 1 14 VCC INA- 2 9 OUTB INA- 2 13 OUTB INA+ 3 8 INB- INA+ 3 12 INB- VEE 4 7 INB+ VEE 4 11 INB+ SHDNA 5 6 SHDNB N.C. 5 10 N.C. µMAX SHDNA 6 9 SHDNB N.C. 7 8 N.C. SO 18 ______________________________________________________________________________________ 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown PART TEMP. RANGE PINPACKAGE SOT TOP MARK MAX4224EUT-T -40°C to +85°C 6 SOT23 MAX4224ESA -40°C to +85°C 8 SO AAAE — MAX4225ESA -40°C to +85°C 8 SO — MAX4226EUB -40°C to +85°C 10 µMAX — MAX4226ESD -40°C to +85°C 14 SO — MAX4227ESA -40°C to +85°C 8 SO — MAX4228EUB -40°C to +85°C 10 µMAX — MAX4228ESD -40°C to +85°C 14 SO — ___________________Chip Information MAX4223/MAX4224 TRANSISTOR COUNT: 87 MAX4225–MAX4228 TRANSISTOR COUNT: 171 SUBSTRATE CONNECTED TO VEE ______________________________________________________________________________________ 19 MAX4223–MAX4228 _Ordering Information (continued) 10LUMAXB.EPS ________________________________________________________Package Information 6LSOT.EPS MAX4223–MAX4228 1GHz, Low-Power, SOT23, Current-Feedback Amplifiers with Shutdown Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 20 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 © 1997 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.